Multiple brushless direct current motors (BLDC) can be applied in one device, such as a seating adjustment system in a vehicle which includes a plurality of motors to adjust a longitudinal position, a seat height, a backrest height, a thigh support, a lumbar support. If each of the brushless direct current motors is provided with one drive circuit, and each drive circuit includes at least one inverter formed by four semiconductor switches, so a large number of electronic elements are needed to arrange in the system. Thus, a structure of the drive circuit is complicated and has a big size and a high cost.